Remote control system



FRF@ my WM.. c; REWMGTON UEFOHMM REMOTE CONTROL SYSTEM Filed June l1, 1927 i Sllee'hs-Sheet l FASB Inman :JP-

Febl, 1931. Q REMlNGTQN LW: Efw

REMOTE CONTROL SYSTEM Filed June ll, 1927 4 Sheets-Sheet 2 Febr 24, 1931., I C, REMINGTQN 1,793,828

REMOTE CONTROL SYSTEM Filed June 11, 1927 4 sheets-sheet V5 Eharles Femm cm mm;

Feb. 24, 1931. c. REMINGTQN 1,793,328

REMOTE CONTROL SYSTEM Filed June ll, 1927 4 Sheets-Shet 4 Imi-iw .Ehazles EIT'TT- gun `Patented Feb. 24, 1931 1 ulsuruo STATES PATENT OFFICE ENGLAND, ASSIGNOR To ASSOCIATED TELE- OE KANSAS oIrY, MISSOURI, A CORPORATION REMOTE fooN'rRoL SXSTEM Application'led .Tune 11,319.12?, Serial No. 198,173, and in Great Britain l.T'aly 16, 1928.

The present invention relates in general to .remote control and supervision systems, and morejspecically to suoli systems in which the 4operation and supervision of power switchinglderices is performed from a dis-` tant station, and the principal ob]ect of the invention, briefly stated, is thel provision of a "new and' Improved remote control and supervision system, the improvements making the o pcrationof the system more posltlve a'nrjl. more reliable, and making its orioinal costaud niaintenance expense substantially' lower. v p

"In"` general, the present invention Vrelates to iniprovenwnts in my copending applications Serial `Numbers 86,383, filed Feb. 6, 1926, and 109,325,1led May 15,1926 although the particular novel features disclosed herein are not necessarily limited in the application to'dis closuresofthose'apl'ilications but can be a/p- 'plied to other systems.

` lThe systemsof the foregoing applications employ a pulsing scheme inI which the sendferent polarity from the rest to designa-tothe ing. switch at the dispatchersstation sends out avtixednumber of impulses each time it is operated, one of these pulses-being of dif.-

signal then'being transmitted. vAt-the suboperated until the reversed impulse is re` ceived and the rstand third switches, afterv station', three swltc'hes are'operated by these impulses, the first and second switches'being i y that 'pulse is received. The reversed pulse controls [the switch overvfrom the second'to I -dispatcliers ofiicewhieh switch is Operated insynchronism -Withthe sending switch until i the third switches through a polarized relay.

4Itlie second and third switches have been properly set thedispatcher may operate vthev selected device by'throwing an operating key.

As4 further object of the present inven-l tion,.I' haveprovided a second switch at the I the j'distinctive' pulse is sent.. This second switch is, then stopped, to prepare circuits which cooperate with the second and third substation switches tomore positivelycheck the. -impulsing4 operation, apprising the; dispatcher if the switches are correctly set.

As a further object of my invention, I simplify the equipment by eliminating the polarprovide, as a further object, circuit arrange# ments for causing the substation senderto repeat the supervisory signals incase the checkrback indicates that the supervisory switch in the dispatchers station has not been properlysetin response to the impulses trans 'mitted by the substation sender., v

Further objects ofl my invention, not s eciiically mentioned here, will b'e apparent rom the detailed description and drawings which `follow.

One example of carrying the inventioninto eect will be described, with reference to the accompanying drawing which illustrates one form of the; invention. It is of course understood' that considerablevariations may be made from this eXamplewithout departing from the spirit O the invention.

Fig. 1 illustrates the selecting equipment at the main station, Fig. 2 the supervisory equipment. Fig. 4 the selecting'equipment at the substation and Fig. 3 the supervisory equipment.l The drawings should be placed'in the followingl order: Fig. 4f at the extreme left and Figs. 3, 2 and 1 successively to the right of this figure. y

Referring to Fig. 1 the selecting equipment comprises two quickacting relays Z and H1, two locking relays KR and WR and three sluggish relays N, SA4 and SA.V In

addition a selecting key l(SKLSKZ, SK3) having two way operation is provided for each circuit breaker to be controlled moving one way to put the circuit breaker in and the opposite way to pull the circuitbreakerout.,

An operating key OK common to all thekeys is also provided, forthe purpose of effecting the actual operation. In addition two rotary line switches are provided namely rotary line switch BLSB and rotary line switch RLSC. Rotary line switch RLSB functions change over pulses,

with each key.v

*asa counting switch and moves through a rect circuit breaker'h-as been selected. 4The other to control the transmission of impulses,

function of the relays is briefl as follows the two slow acting relays SA4 and SA5 are for the purpose of interacting with each while one slow actingv relay N is adapted to. Vbe energized when the operating key OK is depressed toeieco certain operations which' will be' described in detail`- when describing l the complete operation. Of tlie two locking Vrelays the first KR is -provided to energize this time.

energized immediately any key is depressed,v

when .a marked contact is reached by .the wiper' of rotary line switch RLSC'to prevent its operating magnet operating further at A secondvlocking relay WR is and enects certainfunctions initially at the commencement. of the transmission -of the selecting impulses. Of t-he quick acting relays one- '(Z) is energized on the first step of the rotary line switch RLSB and is locked energized 4 normal, while the 'other rela-y H1 isenergized when the apparatus at the substation is set so as to select a particular circ'uitbreaker to be operated 'and remains energized as long as the selecting condition remains to enable the operation to be performed whenever the Forl the purpose of this description, accounts will be land the subst-ation separately, it being con-A sidered suiiicient to indicate the various conbring given of the operations lat the control roomv trols'which are effected in the controlroom to about the desiredresult at t-he substation, the operationsthereat being then described.l It will therefore be, assumed that the firstA operation is to put circuit breaker No. 2in.v For this purpose the selecting key SK2 is moved so as to closeits upper contacts 150, 151. lThe'closureof contact 150 .completes a circuit for the left hand Winding of relay WR asv follows: positive pole.l of i battery B (representedby-thin dotted lines -throuighout the drawings), left-handl windrelay WR, contact 24, conductor C1, Y

ingo n contact 41, contact 56, conductorCQ, contact 150, switch SK2conductor C9, cont-a.ct40,`

the negative'pole, of battery B (represented by-thick -full lines) Relay WR therefore energizes;

at the same time a branch circuit. is completed over the back contact 23 of the relay Z, normal contact of'wipe'r B3 of the by the selecting key operated i and serves to select the indicating 'lamps L1,

until all the keys are restored to` rotary `line switchRLSB, wiper B3, relay SA5, back contact 102 of relay SA4 to positive pole of battery' B. RelayfSA thereby energizes. Relay WR in energizing connects negativepole of battery B to the lead 17 which extends over the contact 59 ofrelay SA2 associated with the supervisory equipment to the lead 17A extending to the substation, and positive pole of battery B over contact 103 of relay SA4 to the lead 18 which extends over anotherback contact 61 of relay SA2 to the lead 18A extending tothe substation. This is the preparatory condition for effecting the apparatus at the substation.A In addition al locking circuit is prepared for the right-hand winding of vrelay WR as follows: positive pole of battery B, Acontact 129', wiper B5, to negative pole of battery B,

`but-is not completed until wiper B5 has been stepped off` normal. When wiper B5 is stepped to an off normal position the locking persists until'the wipers againreach the nor- -mal position. Further a point is opened vat contact 38, thereby energizing this magnet. It also completes a circuit forrelay SA4 at contact'39 and for operating magnet MC at contact 37 Magnet MC and magnet MB are therefore both energized, thel wipers of' these switches however do not step, as lthe arrangement is such that this type of switch only steps on the cle-energization of the magnet. Relay SA4 on energizing vopens the circuit of relay SA5 at contact 102, disconnect-s positive pole of battery B from the line 18A at Acontact. 103, thereby sending a positive impulse tothe substation and connects negative pole of battery b (shown in thick dotted lines throughout'Figs. 1 and 2) at contact 30 to the impulsing lamp IL which-has its other terminal connected to the positive pol/e of battery Z1, the impulse lamp therefore lights; SA5 on de-energizing opens the circuits of magnet MB, MC at ,contacts 38, 37 respectively, andtSA4 causing magnets MB and MC to de-energize' so that the wipers ofl the rotary line switches RLSB'and RLSC advance one step andalso causes relay SA4 to -de-energize. Relay Z no w energizes in the following circuit: positive pole of battery B, wiper B2 of rotary line switch RLSB in on nornal position, relay Z, conductor C1, contact 41,. AContact 56, over conductor C2, contact 150, conductor C9, contact 40 to negative pole of battery B and opens the original energizing circuit at Contact 24 for the lefthand winding of relay-VVR, and the original energizing circuit for relay SA at contact 23, over wiper B3, relay VR rei'naining energized over the locking winding previously described, While relay SA connected to Wiper B3 is connected tonegative pole ofhatl'te'ry Bindependently. Relay Z also opens `a point at Contactl 2 5 in the. circuit of the in terrupter contacts 152 of magnet MC, itV also connects positive pole of battery B 4to vthe nor.- mal contact '153 engaged by Wiper B2 at contact 20, and relayHll at contact 21'to back wiperfB1I completes a circuit: negative' pole.

of battery B, contact 40, conductorl C9, contact 151, contact 154, wiper B1, winding of relay KR, contact 311 to the lead la)l Current is therebyl transmitted overa circuit including the leads and 18A at this" instant, which serves the double purpose of operating relay'KR andofoperating a switch-over re `lay at the sub-station. It s'hould'be 4men-` tioned that other impulses similarto the first described impulse to the substation, areLSent each time, relay SAfl opens and closes its contacts, so that one impulse vis sent to the substation for each step made by' the rotary line switchesRLSB and RLSC. `When relay KR operates itcloses ay locking circuit for itselfas follows: negative pole of battery B, wiper C5,`contact 35, left-hand winding of relay `K-R,`positive poleofbattery B'. Relay KR- therefore remains energized as long as the rotary line switch' RLSC is 'in an olfnormal position; relay'KR opens the impulsing circuitfor magnet MC at'contactBG. Magnet MC therefore ceases to operate to 'further impulses and remains with its wiper C1, C2

' resting. on the fourth contacts. The rotary line switch RLSB however continues to rotate until a numbern of impulses correspondf -ingto the movement offa rotary line switch RLSB through a complete cycle lis completed. Whenthis occurs, Vprovided the apparatus at the substation has operated correctly, battery will be'connected at the substation to the leads 17A andlSA." In the meanwhile at the control Vroom the locking circuitfor` relay WR- will have been opened -due to wiper B5 reaching the normal contact, relay W R acl cordingly cle-energizes. Relay Z. is however still energized because positive battery is supplied to the normal contact of Wiper-BQ'over itslown contact 20, relay Z being of course- Aconnected to negative'pole of batteryA aslong as a selecting `key is depressed.- It will be noted that this' relaycannot therefore restore unti-l all the selecting keys have been put back to normal. Relay'WR in de-ener .tarily.

izing disconnects negativepole of battery from the lead 17A at contact 22 and at of the lamps marked In and Out, associated Withthe selecting keys, connects nega tive pole of battery B over Contact 29, conductor C3 tn contact 43 of relay RF1 for a purpose to be described. later. The lamp marked In associated with the selecting key SK2 has its other terminal connected over 'the fourth contact 105, Wiper C1 to negative pole of battery B, and accordingly this lamp energizes and as it. corresponds to the selecting key SK2 and to the direction'in which the selection key has been operated, namely to operate the upper or in springs, it serves as a direct check tothe attendant. The attendant can now operate the selected apparatus at the substation and for Athis purpose he `presses his operating key OK. When this occurs, a` circuit is completed for relay Nas follows positive pole of battery B, operating key AOK, relay N, negative ple of battery B.- Relay N energizes,opens the in- `itial energizing contact of'relay KRat contact 34 and completes a circuit as follows: negative pole of battery B, contact 40, conductor C9, contact 151 of the selecting key SK2, fourth contact 155, wiper C2 at contact 33 to the lead 40, thereby eii'cctingthe operal tion of theselected apparatus at the substation, as it also connects positive pole of battery B at Contact 32 to the lead 18A, thus,

completing the return circuit for effecting the operation.- It completes a circuit for relay RP3 as follows: positive pole of battery B, Contact 31, conductorC, relay RPS to negative pole of battery B for a purpose to be described later.A RelayN being slow acting -ensures that the operating circuit is lclosed fora suiiicient interval of time, even if the operating key,is only pressed momen y y Preferably this operating key is ofthe self restoringtype and cannot therefore remain inthe operated'position after` once `the attendant has ceased to press it.

' 'Having seen that everything has operated correctly whether the selection only or the selection and operation, the attendant restores his selecting key to normal, whereupon delay Z de-energizes; relay Z in deenergizing opens its own locking circuit' at Contact 23, so that it cannot energize immediatelyanother key is depressed, and closes its "back contacts 24 and 25. The closure of both these contacts is without effect. .It Will have been noticed that relays SAF) and SA4 Was deiressed. A circuit is closed for magnet M negative pole of battery B, Wiper C5, contacts 26, 25, interrupter contacts 152,

magnet MC, to positive pole of battery B.

v-Magnet MC therefore operates under the control of itsown interrupter contacts to advance thewipers tonormal. The circuit of relay H1 is opened at contact 21 by' relay Z, and thereforethis relay -de-energizes and everything'isnow restored to normal. l

Before considering the reception ofzselect- Aing signals atA the substatiomfor which reference should be had to Fig` 4, it "Will be Well I' to review briefly the circuits completed to the leads 17A. and 18A. Secondly, positive the leads17A, 18A and 40 at the control room. These are: firstly, battery is connected across impulses are'transmitted overleadlSA While negativel battery is maintained over lead 17A.

Thirdly, whenfa marked'contact is reached,

negative battery'is connected to. lead 40. Fourthly, When a complete cycle of impulses (say25) have beensent over the leads 17A and 18A, battery is connected across the leads 17A'and 18A- at the substation'andrelay H1 is connected across the leads 17A and 18A at theA control room in placeof battery. Fi-fthly, to ope-rate the selected apparatus,

negative pole of battery is connected to lead lay I-I'lacross the leads 17A and 18A is opened 40 momentarily. SiXthly, the circuit for reto restore the selecting equipment at the substation. A v

It Will be notedthat the line relay LR (Figure 4) is connected betweenthe conductors 17A and 18A as follows ,conducto'r w 18A,'contact 29,-conductor 18B,7relayl LR,

' contact 209, contact 28, conductor 17B, contact 27, conductor 17A, consequently When lio.

battery is connected across the leads17A and 18Aat the control room,-the line relay` energizes and at vbntact 201 completes a circuit at 'contact-202 for magnet y., line switch RLSB over coneontact 204 'for magnet MA e switch or counting switch of the-rotary RLSA. Wherf-the pulses are received the magnets'MA and MB step thewipers of their Arespective switches one step vat a time, when the Contact marked by the selecting key at the controlroom is reached as reviously described, a c1rcu1t 1s completed roml negative pole of battery B, over conductor 40, over contact 205, theright-fhand Windingof relay COR, to lead 18B, contact' 29, and conductor 18A which is connected to positive pole of battery B. Relay COR accordingly ener# gizes and substitutes the magnet MC of the rotary line switch or checking sWitchRLSC in place of magnet MB `byopeningicontact 203 and closing contact 20B. The rotary line switch BLSB therefore functions as a selecting switch and rests With its .wipers onthe fourth contact, While magnet MA continues '565 to stepon but lthis time with the magnet MC.v for Relay COR completes a lockino' itself at contact 207 over the back contact 118 of relay BR. The line relay proceeds toreyceive pulses, so that in'all it receives 25, the' lnu-mberof steps taken by the rotary line sWitchRLSB at the control room, and RLSA `and RLSB and RLSC jointly at the substation. When this cycle has linished, the rotary line switch RLSA. Will have restoredfto normal. The rotary lineswitch RLSB Will circuit for' have its Wipers resting on the fourth conta-ct,-

l and the rotary line switch RLSC Will have its Wipers resting on `the twenty-first contact.

lIn this position as battery is disconnected from across the leads 17A and 18A at the control room, th-e line relay LR (le-energizes; shortly after the relay ,"SAR de-energizes.

The circuits of the magnets MA, MB and MC are opened.- Battery Will'then befed to the Ac'ontrol'room as follows z-.positive pole of battery B, Wiper C3, Wiper B3 and the con' tacts on Which these'Wipers are resting, Wiper Y A1 and its lnorm/al contact to conductor 18B,

contact 29 to conductor 18A, and negative pole of battery, contact 210, conductor C13, relay HR, `conductor 17B, contact 27, con'- ductor'17A. Relay HR at the substation'l energizes in series With relay at the control. room, disconnects the line relay from across the conductors 17A and 18A at con# tact 28, opens a point. in the circuit'otrelay BR at Contact 211, disconnects conductor 40 vfrom the cut-oli` relay COR at contact 205 and connects it up' at contact'212 over conductor C14.' to. .relay O1, the 'other winding ofwhich is connected ,to conductor 18A.v

' Consequently at this-time itis possible for the operator at the control room, by pressing the operating key, 'and thereby 44connecting battery between the conductors 40 and 18A to operate relayv O1, thereby effecting. the

utting inv of f circuit breaker No.' 1 as fol-A voWsr-negativey pole' of battery B, contact 213, conductor C16, terminal 214, interposing relay for operating circuit breaker No; 1 (not shown)-,vterminal215, fourthcontact 216 of wiper B1, wiper B1, contact 217 to positive 'poleof battery B. Relay O1 also serves the purpose of preventing the sending of sup'er.

i the circuit in *Whichi relayHR is energizedis opened as Well of course as the circuit for `re' lay O1 and the interposing relay. Relay O1 in deenergizing simply permits the transmission ofsupervi'sory signals'whereas the relay HR in de-energizing completes acircuit relay BR as follows positive polepof battery B, wipers B5 or C5 (in parallel as long- -as both switches areot-normal) relay BR, conductor (3l- 0,r contact 21,8, conductor C12, contactsV 219, 211 to negative ole of bat-l tery Relay B Renergizes an. completes,- a circuit at contacts 220 and 221 for-Linter-v rupter contacts and magnet MC and for in terruptercontacts and magnet MB. Magnets 1MB and MC therefore operaterto kopen their interruption Vcontacts and step the -wipers B1, 132,133 and Band-wipers C1, C2, C3 and C5 respectively'tonormal. It will benoted that relay BR also closes a 'contact 122, which is `without eliect as thewiper A2 is .then in normal position.- If however for any reason the wiper .A2 had' stuck inV angintermediate position,tlns' circuit would have served to restore it tol normal byenergizing the magnet Ma through its interruptor contacts.A Relay BRI by opening Contact 118 opens a locking cir..

cuit for relay COR which deenergizes, the

line relay and relay SAR having already de- .energized immediately 'subsequently to the transmission of the selecting impulsesl and consequently everything; is now restored to normal.-

vA -description Will'nowbe given of the transmission of supervisory signals when' a circuit breaker changesits position, Whether automatically or under the control of anattendant.- A description willbe first given .with `reference of Fig. 3 which shows the substation equipment. When the circuit brealcA erNo. 2 i's put in due to the operation previously described, a rotary brush controlled thereby momentarily connects two segments together, therebylcompleting a circuit for relay RSRlv as follows :-'negative pole of bat- B, segments 261, 260, Contact 224, relay' 1, wiper D4, normal contact 225 to positive .pole of battery B. Relay RSRl energizesand completes a locking circuit for itlselt'over. contact 226 independently of theV transsitorily closed contact between the segments, It also 'completes a circuit, provided the rotary line switch RLSA is in normal osition for slow relaySARl and relay L R at .contact227- AThese circuits may be traced asv follows negative pole of battery B, contact 228, conductor C18, normal Contact 229, Wiper A3, conductor C19, contact'227, normal contacts 230, 231 where the circuit. divides, one part passing over wiper D1, relay LLR to positive pole of battery and the other part passing over wiper D5,relay SARl, contact 232 to positive pole of battery B. These cir-- cuits are so arranged that only provided the rotaryline switch RLSAjjis at normal, and that relay O1 is not energized, that isprovided no selecting signals are being transmitted and provided that no circuit breaker is being operated, can the relays SAR and LLR energize. Relay SAR1 on energizing completes a circuit for magnet MD at con tact 233. Magnet MD accordingly energizes.

relay SAR2 which energizes. It should lbe mentioned that a circuit in parallel to the circuit through relay SARl extends to relay l CO1 and thence over contact 235 topo'sitive pole ot'r battery. Relay `CO1 on` energizing opensl cont-act 210 4to prevent relay HR 'from energizing and to prevent battery being transmitted back over the eonductorslr A and 18A, disconnects the conductor 18A-from thecondut-tor 18B and the line relay LR at contact 29, and connects positive battery to said conductor at conta-ct 236, disconnecting conductor 17A from the selecting equipment, and connects it at contact 237to contact 238 opened by relay LLR which energizes atthe same time as relay CO1. Relay LLR in `addition connects negative pole of battery B over conduct'orCl to the lead 40 at contact 239 over contact 205. It will therefore be seen that on the initial step, a circuit 4is completed over the conductors 18A and 40 due to the fact that negative pole of battery B is connected to the conductor 40 and `positive battery to the conductor 18A; This prepares the supervisoryr equipment at the control room. is energized shortly after this by relay SARl,

over contact 234, and opens the circuit/of relay SARl at contact 232 and a point in the circuit alread opened by LLR at contact 240. 'Relay Relay. SAR2 ARl accordingly deenergizes 1 ,and opens the circuit ofmagnet MD which in aposition to energize whenever relay` SAR2 is deenergized fwhile the relay CO1 remains locked energized. Relay SARl en deenergizing opens the circuit of relay SAR2, so that this relay shortly after deenergizes. Relay LLR also being deenergized battery is connected across the conductors 17A and 18A, positive to conductor 18A `and negative t conductor 17A, to effect the next operation at the control room. It will be noticed that relays -SARl and SAR2 intermittently energize and consequently pulses areA continued so that the wipers step successively back to the normal position and pulses are sent correspondingly over conductors 17A and 18A. During its stepping-each time the wiper D1 reaches a contact connected to negative pole of battery B, a circuit is completed for relay- LLR Afrom the segments of the circuit breakers which are in so that LLR energizes and -connects negative pole of battery to lead 40,

.tive pole of battery is conncctedto theconmediately wiper D1 leaves the contactfcorrespending tothe circuit breaker which is in, that is when relay SARZ is deenergizing, and is therefore without effec-t as regards impuls f ing over the conductors 17A and 18A.` 'Nega-k tacts stepped over bythe wiper Dl for each time that a circuit breaker is in, for instance when circuit breaker No. 1 is in, negative pole of battery is connected via rotary brush bey tween the two upper segments 222, 241 asv shown and thence to the third contact engaged by wiper'Dl. It' circuit breaker No. 2 was in, negative pole of battery would have been connected over segments 261, 262 to the -fourth'contact and similarly Withtheother circuit breakers, sotliat LLR sends an impulse l over the lead 40 for 'each circuit breaker that was in, that is it completes a circuit between the conductors 18A fand' 4() momentarily. When -thefswitch reaches normal position, CO1 and SARl restore to normal, ,and everyl thing is then restored to its originalconditioh with battery disconnected from all three consoon as the circuit'breaker is actually in negative pole of battery B, segments` 261, 262. engaged by rotary brush, conductor C21',

twenty-third contact engaged byk wiper C1 of rotary line switchRLSC, wiper Cl, Conductor'Cll', relay X, wiper D2 of rotary line switch RLSD, its normal contact, contact 243 of relay Ol to positive pole of battery B. Rela lay X on energizing effects the following circuit changes: It vcompletespat contact 244 a locking circuit for itself independent of the circuit over wiper C1, and at contact 245 a locking circuit for itself dependent on wiper D2 and its :normal contact but' independently of the Contact of relay O1, at contact 224 it opens the circuit of relay RSRl, and at contact 2461prepares a circuit for relay Y so that this relay will energize if the circuitA breaker should immediately come out, and a lmomentary circuitbe completed between. the

Vlower segments 261, 260 engaged by the tion of the transmission of'supervisory signals, .the operation proceeds as before, eX`- cept that as negative pole of battery is connected over the circuit; contact 244, conductor C11, wiper C1 and its twenty-third contact, to the fourth contact in the bank of wiperDl corresponding to the particular circuit breaker discussed, and relay LLR to posi- .tive pole'of battery B, the signal sent will be .that the circuit breaker isin although actually it may be out. (This signifies that the circuit breaker has actually moved to the invposition When wiper D2 reaches its twenty-fifth contact, the locking circuit of rclay X isopened and this relay releases as also does relay Y. Relay BR energizes and the selecting equipment returns to normal. Relay RSRl having de -energized as before on the lirst step'of D4 has energized again ,owing to'relay Y being held energized, while the locking circuitfor relay RSRl is open, and so the supervisory signals are repeated and this time the circuit breaker in question is signalled as being out..

It willbe noted that the operations atthe substation are as'follows z-'Firstly battery is initially connected across the conductors 18A and 40, secondly battery impulses are sent over the conductors 17Aand 18A, and thirdly each time a rotary line switch'is in a position corresponding to a circuit breaker that is in, battery is again connected across the conductors 40 and 18A and n'o impulse is sent over conductors 17 A and 18A at that time.

With this preliminary recapitulation of the signals sent from the substation a description will now be given with reference to Fig. 2 of the reception ofsnpervsorysignals at the controlling station. 4:[t will .be noted that re y R1 when wiper B4 of'therotary line switch lLSBs'in normal position and the operatingkey is not depressed, is connected across theleads 18A- and40 :in the-circuit, lead 40, contact 34, conductor C8, relay Rl, conductor C7, normal contact B4, wiper` B4,

across the leads 18A and 40, relay R1 is energized, completes a circuit for relay SAS at contact 52, and connectsne ative vpole ot 3 of the rotary battery at contact 53 to wiper line switch RLSA. It valso completes a circuit as follows :--positiv'ev pole of batteryB, magnet MA, contact 55,. contact l54, to negative polel of battery B. Magnet MA'ot the rotaryl line switch RLSA-thereupon ener- 'gizesbut does not however advance the wipers'untilit is released. Relay R1 connects negative p'ole of battery B at contactl to the lefthand windings of relays R3 and R4 and to relay SAL SAB on energizing. com'- pletes a circuit for relay SA2 Iat contact 49, which relay disconnects the' leads 17A and 18A at contacts 61, 59 respectively from their extensions 17 and 18 to the selecting equipment sovasto render the selecting equipment inoperative, and connects them to relay R2. at

' lcontacts G2 and 60. Relay SAQ also completes .an energizing circuit for'relay R5 at contact Aleft-hand windingl of rela-y RPL R4 also energizes and completes a circuit of contact y j T3 for 4the circuit breaker pilotlamp CBPL which lights to indicatetllata supervisory signal is heilig' received from the substation.'

Relay R4 completes a locking circuit for itself at contact 99 through the contactsll of the circuitbreaker alarm key. Relay R3 energizes 'by current 'flowing through 'its' lefthand winding and the contact 162 of the mas- .ter key and locks energized over the contact ,161 of the circuit breaker alarm lkey. At 4the .saine time' it connects positive pole of.

` battery B at contact 101 to the circuit 'breaker pilot bell CBPB, whereupon'the'bell rings and calls the attention of the attendant to the chan-ge of position of a circuit breaker at vthe substation. All these operations take place due -to battery being connected across the leads 18A4 and' 40 of the'substation. The

"next control exerted from the substation is i 3othe transmission of impulses over the leads 17A Vand 18A causing the relay R2'to pulse,-

the relay/R11cle-energizing immediatelybhe .magnet of the rotary line switch atl the subvSA 1, connects negative pole, of battery to wiper A2' at contact" 63, establishes-a new circuit for the magnet MA at contact 66 andf :connects negative pole'of battery to wiper A1 at'contact 67. As described 25 pulsesare received byrelayvR2 which thereby causes magnet MA to step 2,5 times and so restore to normal. but at .various times the circuit isconipleted overtheleads 18A and 40 causing the relay R1 to energize as each wiper D1v at the substation (Fig. 3)V makes connection with a Contact connected to a circuit breaker which vFor the circuit breaker described the rotary line switch RLSD at the substation `will advance three' steps when a circuit will be completed over the leads 18A and 404 for the relay Rl. The wipers A1, A2 and A3 will then'be resting on the fourth contacts; relay R1 will he energized at this time and a circuit will be completed as follows :-negative pole of battery B, contact 53, wiper A3, fourth contact, left-hand winding of relay DR to positive pole ofrbattery B. The relay DR having .differential windings and being nor.- nially energizedthrough its right-hand windl ing and contact S9 deenergizes at this time s0 that indoing so it'disconnects the green lamp, and connects a circuit for the red lamp. By pressing thel circuit breaker alarm key the locking circuitfor relays R3 and R4 is opened 'which thereupon deienergize and .everything restores to normal. i

It should be mentioned that the relay SAQ was locked energized after the first step over wiper A5 and bank contact engaged thereby. The operation of the circuit breaker ala'rln -key causes the circuit breaker pilot lamp to be .extinguished and the .ringing of the circuit breaker pilot bell to ceasey If a circuit breaker were already in, say` lit and the effect of the'w'ipers A1, A2 and A3 wouldbe exactly the'same as in the case just described of circuit breaker No. 2. It a circuit breaker is out, take also, for instance, cir'f cuit breaker No.1, then the green lamp would .be lit owing tothe differential relay DRl be ing energized and in this case as no circuit would be completed over Wiper A3, relay R-l not being energized, while Wipers A1 and A2 although connected up by R2 would have no effect, relay DRI simplyzremaining energized and the circuit of LRl is open so that relay LRl, cannot energize and the green lamp remains lit. If on the other hand a circuit breaker that was'in has'come out or been pulled out` then the circuit through left-hand windin ofV relay LRl would be closed over wiper Q1 for`a sufficient period through the make bcforebreak contacts of relay DRl to energize this relay, while relay DR-l would be cireriitblieaker No. 1, the red lamp would be energized `through vits right-hand winding@ over Wiper A2 and would change the red lamp for a green lamp; Relay LRl on energizing opens the lamp circuit at contact 72 and con'- nects it at 82 to a flashing circuitwhich is initiated due to the closure of Contact 96. Relay LRl completesa lockingcircuit for itself over contact 90 and contact 162'of master key. Relay LRl at contact 96 completes a circuit for relay'SAG over contact 65. Relay SAGr completes a circuit for relay SATY at contact 64'; relay 4SAGand SAT intermittently energizel so that the circuit completed by relay SAG is an intermittent one causing lamp GLl to flash. The attendant byV pressing the master key can open the locking circuit of relay LRl with the result that the green lamp glows steadily and further the intermittent .action of relay SAG and SAT is caused to cease due to the' opening of Contact 64.

lt may happen that the rotary line switch RLSA at the control station does not keep pace With lthe rotary line switch RLSD at. f the substation. It is important in such a case ICO oil normal position if ithas not step ed properly with the rotary line switch-RL B at the f substation when aitrain of impulses is com? pleted. .RPI energizesand locks energized at contact 4Q. It opens contactwlO, thereby preventing any selecting operation fronibe. ing effective. In addition it \conne cts negat-iveA p ole of battery B to the twenty-fourth contact engaged bv wipers ,B1 and CQ of rotary lineswitch RLSB and RLSC respec- `tively over cloiitact 145 and conductor C23, j and also. connects negati-ve pole of battery B to the lower terminal of the winding of relay Z ove`rcontacts 58, 14Q, conductor vC1 in a similar manner to the operation of a selecting key, 4thereby vcausing `the transmission of a selecting signal corresponding to the marking of the twenty-fpufrth contact which serves at the substation to selecta relay RR to cause the transmission oa supervisory signal when the apparatus has been correctly set. When relay H1 operates after the selecting signal has been sent, a circuit for relay RPQ is completed as follows po'sitive pole of battery `B, contact 170, relay RPQ, contact 43, conlductor C3, contact Q9, negative pole of battery B; `Relay RPQ closes a circuit for relay N as follows positive pole of battery B, contact 171'conductor C4, rela N to negative pole of battery B. `Relay v therefore energizes which is equivalent to the operation of an operating-key, and so completes a circuit for relay RR which energizes relay RSRl at contact l174,y and so causes the transmission,

of signals to be repeated. Relay N com-v pletes a circuit for relay RP8 as follows negative. pole of batterytB, relay RP3, con'l ductor C5, contact 31 to positivepole of batl tery B. Relay RPS opens thercircuit of re'- lay RPQ at contact 170; relayv RPQ thereupon de-energizes. Magnet MA lrestores the rotary line switch RLSA to normal prep'ara' l position after the second transmission of the signal, the above cycle of operation will be repeated, in fact the repetition of the trans- ,mission of the signal will continue until the switch RLSA steps with switch RLSB, or untiltlie attendant halts the operation.

Having now particularly described and.

ascertained the nature of my said invention and in what manner the same vis to be performed, I declare that what I cla-ini is:

l. In a remote control system, a stepping switch, a plurality of switching devices accessible thereto, animpulse transmitter, a

checking switch operated thereby,a manual key, means operated responsive to the operation of said key for marking a certain contact in said checking switch and for starting said transmitter to impulse said stepping switch and checking switch, means for. stopping said switches when said marked contactis reached to select a switching device and lfor holding said checking. switchthereon as long as said key remains operated, meansfor checking the position of said stepping switch, said means including contacts on said checking switch and contacts on said key, and means for operating said selected device. `Q. In a remote control system,l a plurality of multi-position switching devices, a device selector. associated therewith,

sender associated with'said devices, a Supervisory selector associated with said indicating means, means operated by one of said devices changing its position fo r.opeating lsaid supervisory sender to transmit a code ind1 cat ing the positionsoccupied by all said dei vces,.1neans responsive to said codevfor operating said supervisory selector to set said indicating. means in accordance with the pol indicating means corresponding thereto, a supervisory sitions of all said devices, a checking means operated to determine if said supervisory selector hasfunctioned properly, a particular y device, means controlled'by said checking means if said supervisory selector'has not functionedl properly for setting said device v selector to select said particular device,'means for checking the operation of said device selector and for operating said selected device, and means controlled by said selected device for reoperating said supervisory sender to a'gain transmit said code,

3. In avremote control system, a plurality 4of multi-position switching'devices, a select ing switch and a supervisory sender associated with said devices, supervisory signals correspond-ing to said devices, a supervisory switch and a selecting sender associated with p v Said signals, normal positions for said senders and switches, a supervisory start relay,

means responsive to ach'an'ge in position of one of said devices for energizing said relay, meanscontrolled by. said relay ffor starting said supervisory sender out of its normal position, means controlled by said sender for stepping said supervisory switch, means controlled jointly by said sender and supervisory switch in one cycle of'operation for arranging said signals to indicate the positions` occupied by all of said devices, and means operated if said supervisory sender and switch do not reach their normal position simultaneously for operating said selecting sender and switch in a particular manner to restart said supervisory sender and switch.

fl. In a remote control system, amcontrol station, a substation, an impulse transmitter in the control station for transmitting a constant number of impulses, aA pair of switches in the control'station, a receiver in the substation comprising a. plurality of switches, devices in the substation accessible to the receiver, means for operating the transmitter to generate a constant' number ot impulses and 4to divide the constant number iii two switches'i'n the substation recenterresponsive tothe first part of the constaiit'number lot tion and a substation, devices 'at the substajparts dependent up'on the device to he selected, means for operating the iirstot 4the impulses generated by the transmitter to select one of said devices, means for operating the second'of 'said switches in the substation receiver and said switches iii the control sta- ,tion in synchronism therewith, means for operating a third of said switches inthe substation receiver responsive to remaining part y ofthe constant number of impulses generated by the transmitterand for operating'the sec- .ond switch in the substation receiver aiid `one of said switches in the control stationin syn'- 'chronism therewith, a checking circuit, and

means for completing said checking circuit only in case all of said switches have operated synchronously as setfforth.

.5., In a remote control system, a control station, an impulse sender in the control'stat-ion including means for transmitting a lixel number of impulses in each. operation and for dividing the constant number into twoparts dependent upon the device to be selected, a'

selecting switch in the substation, means tor operating said selecting switch in response tothe lirst part ofsaid constant number 4o t impulses to select a device, a checking switch in the substation, means for operating said checking switch in response to the remaining` part of said constant number of `impulses, other checking switches in thejcontrol and substations, means for operating certain oi said other checking switches iii-synchronism with said selecting switchand for operating certain of them in synchronis'm with said first checking switch, and means in the control station operated if all the switches operate inA synchronism to indicate the selected device! 6. In a remote control system, Va control station and a substation, devices at 4the substation, an impulse sender in the control stationincluding means for transmitting a fixed number of impulses in each operation and fori dividing the constant number into two 'parts dependent upon the' device to be select- A' ed, a selecting switch in the substation, means i .for operating said selecting switch in response to the first part of said constant num 'bei' of impulses to select a'device, a checking switch in the substation, means for operating 'said checking switchrinlresponse to the remaining part of said constant number ot' impulses, other checking switches in the control and substations, means foroperating certain nously. 1

.of said other checking switches in synchroiiisni with said selectingr switch and for operating certain ot them in synchronisni with said first checking switch, iiieans-iii the con-v trol'vstation operated if all the switches operate in synchronisin 'toindicate the selected device, and ineans operated from the control station .to control the selected deviceonly in case all the switches vhave operatedsynchro- 7. Ina reniotecontrol. system, a control station vand a substation; devices lat, the substation;` a sender in the control station includingvmeans for transmitting a fixed number ofV impulses and for dividing the fixed n uinberinto two parts dependent upon the deviceto be selected;v a control switch at the control station, means for operating said control switch in response to the irst part of said fixed'fnuinber of impulses to stop on a predeterminedY contact;V a checking switch at the substation, means for operating said checking switch in response to the remaining part of said fixed number ot' impulses; a selecting switch in the substation; a counting switch inthe substation, a counting switch in the control station, means forjoperati'ng' both said counting switches and said selecting switch in the substation in synchronism with said control switch to cause said' selecting switch to select one of said devices and for operating both said counting switches iii synchronism with said checking switch; means in the control station operated if all the switches operate in synchronism asset Aforth to indicate the selected device,vand

means at the control station for controlling the operation of the selected device only in case all the switches have operated synchronously.

8. In a remote control system, a control station anda substation, trunk conductors between said stations, a plurality of switching devices at the substation, means including `an impulse transmitter for transmitting im-l pulses over a pair of said trunk conductors and for generating other impulses, a selecting switch at said substation, means responsive to the impulses transmitted over said pair of conductors for operating said selecting switch, a control switch in saidcontrol `station, a plurality of switching devices accessible thereto, an impulse transmitter at said'control'station, means for operating said transmitter to send a group of impulses over a pair of conductors of said trunk, means responsive to said impulses for operatingsaid stepping switch, a control switch in said control station, means for operating said control switch in synchronism with said step-V infr switch a counting sw itch in said control t 7 D corresponding to Vsaid station, contacts switching devices accessible to said counting switch, means for markingja. particular one of said contacts in accordancef'with the device lto be selected, means controlled by said transmitter for Aoperating said counting switch, means responsive to the counting switch engaging said marked contact for sending an impulse over one conductor of said pair of conductors and a third conductor of saidtrunk in series, means responsive thereto for stopping said stepping switch to select the corresponding device and for stopping said control switch in a corresponding position, and means for controllingv the operation of said selected device over a circuit including said third conductor and a wiper of said control switch.

tor of said trunk in series, means responsive thereto for stopping said stepping switch to select the corresponding device and-for stopping said control switch in a correspondingy 11. In a remote 'control system, a control station and a substation, a trunk between said stations, a stepping switch at the substation, a plurality of switching devices accessible thereto, an impulse transmitter at said con-` trol station, means for operating said-transmitter to send a group of impulses over a pair of conductors of said trunk, means re p sponsive to said impulses for operating said stepping switch, a control switch in said control station,.,means for operating said control switch in synchronism with said step'- ping switch, a counting switch in said control station, means controlledby said trans- `mitter for operating said counting switch to send an impulse over one conductor of said pair of conductors and a third conductor ofv said trunk in series at a predetermined time,

Imeans responsive thereto for stopping said stepping switch to select a device and for stopping said control switch in a correspond- 'ing position, means operated over said first pair of conductors for automatically checking the accuracy of said selection, and means for controlling the operation of said selected device over ar circuit including said third conductor and a wiper of said control switch.

In witnesswhereof, I hereunto subscribe my name this 9th day of May, A. D. 1927. CHARLES REMINGTON.

10. In a remote control system, a control station and a substation, a trunk betweeny said stations, a stepping switch at the substation, a plurality of switching devices accessible thereto, an impulse transmitter at said control station, means for operating said ltransmitter to send a group of impulses over control station, means for operating said control switch in synchroiiism with said step! ping switch, a counting switch in said control station, contacts corresponding to said switching devices accessible to said countingl switch, means for marking a particular one of said contacts in accordance with the device to be selected, means controlled by said transmitter for operating said counting switch, means responsive to the counting switch engaging said marked contact for sendingV an impulse over one conductor of said pair of conductors and a third conducy iso 

